Fundus imaging system

Abstract

The invention provides a fundus imaging system, a pupil separator is applied to the fundus imaging system, an illumination light beam is reflected to a human eye through the surface of a first pupil separation element and then is reflected by the fundus, and the light beam reflected by the fundus is emitted through scanning to form parallel light in different directions in a scanning range. Multi-angle parallel light which is symmetrical with the main optical axis as the center enters the pupil separator, is emitted through a first light pupil of the first pupil separation element and a second light pupil of the second pupil separation element, and enters the camera for imaging. Wherein the diameters of light spots of the two parallel light beams which are symmetrically incident by taking the main optical axis as the center and are emitted through the pupil separator are the same, so that the light intensity of the whole view field is uniform, the numerical apertures in different view fields are consistent, the uniformity of the light spots is improved, the definition of each part of a formed image is relatively consistent, and the quality of the formed image is relatively good.

Description

Technical Field

[0001] This application relates to the field of optical imaging technology, and more particularly, to a fundus imaging system. Background Art

[0002] Fundus imaging is an important clinical diagnosis and treatment basis in the field of ophthalmic disease diagnosis and treatment, used to detect the condition of the eye to obtain detection data and support the diagnosis and treatment of ophthalmic diseases.

[0003] In the existing fundus imaging system, the pupil separator is usually a planar optical element with an elliptical outer contour. The middle strip area along the major axis of the ellipse of the pupil separator is an extinction area that absorbs light beams. A through hole is opened at the center of the extinction area as a light-transmitting area for collecting light beams, and the two sides of the middle strip area are reflective areas. The pupil separator is disposed at an angle of 45° in the main optical path of the fundus imaging system. The illumination light beam is reflected by the reflective area of the pupil separator and then turns to enter the human eye, and after being reflected by the fundus, it enters the pupil separator again, and then exits through the light-transmitting area of the pupil separator and is received by the camera to generate a fundus image.

[0004] Due to the inclined setting structure of the pupil separator, the numerical apertures of the light beams transmitted through the pupil separator in different directions are different, resulting in uneven light beams on both sides of the light-transmitting area of the central through hole, so that the clarity on both sides of the field of view of the fundus imaging system is inconsistent, thus affecting the poor image quality of the fundus imaging. Summary of the Invention

[0005] This application provides a fundus imaging system, including a pupil separator that is easy to adjust in the fundus imaging system, which can make the light intensity of the entire field of view uniform, the numerical aperture consistent at different fields of view, and the quality of the imaged image better.

[0006] To achieve the above object, the technical solution adopted in the embodiments of this application is as follows: The embodiments of this application provide a fundus imaging system, including a pupil separator. The pupil separator includes a first pupil separation element and a second pupil separation element arranged at an included angle. A first pupil is provided on the first pupil separation element, and a second pupil is provided on the second pupil separation element. The parallel light beams in different directions scanned and emitted exit through the first pupil of the first pupil separation element and the second pupil of the second pupil separation element. Among them, the diameters of the light spots of the two parallel light beams symmetrically incident with the principal optical axis as the center are the same after exiting through the pupil separator.

[0007] The beneficial effects of the embodiments of the present application include: the fundus imaging system provided by the embodiments of the present application includes a pupil separator, the pupil separator includes a first pupil separation element and a second pupil separation element arranged at an angle, the first pupil separation element is provided with a first pupil hole, the second pupil separation element is provided with a second pupil hole, and parallel light emitted in different directions by scanning is emitted through the first pupil hole of the first pupil separation element and the second pupil hole of the second pupil separation element, wherein the diameters of the light spots of the two beams of parallel light symmetrically incident with the main optical axis as the center after being emitted by the pupil separator are the same. The pupil separator of the embodiment of the present application is applied to the fundus imaging system, the illumination light beam is reflected from the surface of the first pupil separation element to the human eye and then reflected by the fundus, the light beam reflected from the fundus is scanned and emitted to form parallel light in different directions within the scanning range, and the multi-angle parallel light symmetrically with the main optical axis as the center is incident on the pupil separator, and is sequentially emitted through the first pupil hole of the first pupil separation element and the second pupil hole of the second pupil separation element, and is imaged by the incident camera. Among them, the diameters of the two beams of parallel light symmetrically incident with the main optical axis as the center are the same after being emitted through the pupil separator, so that the light intensity of the entire field of view is uniform, the numerical aperture in different fields of view is consistent, the uniformity of the light spot is improved, the clarity of the image is more consistent in various places, and the quality of the image is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0009] Figure 1 One of the optical path schematic diagrams of a pupil separator in a fundus imaging system provided in an embodiment of the present application; Figure 2 A second optical path schematic diagram of a pupil separator in a fundus imaging system provided in an embodiment of the present application; Figure 3 A third optical path schematic diagram of a pupil separator in a fundus imaging system provided in an embodiment of the present application; Figure 4 A fourth optical path schematic diagram of a pupil separator in a fundus imaging system provided in an embodiment of the present application; Figure 5 A fifth optical path schematic diagram of a pupil separator in a fundus imaging system provided in an embodiment of the present application; Figure 6 A schematic diagram of the structure of a pupil separator in a fundus imaging system provided in an embodiment of the present application; Figure 7FIG. 6 is a schematic optical path diagram of a pupil separator in a fundus imaging system provided by an embodiment of the present application; Figure 8 FIG. is a schematic optical path diagram of a fundus imaging system provided by an embodiment of the present application.

[0010] Reference numerals: 01 - pupil separator; 02 - scanning galvanometer; 03 - camera; 10 - first pupil separation element; 11 - first pupil; 20 - second pupil separation element; 21 - second pupil; 30 - receiving substrate; d0 - diameter of the second pupil; d1, d2 - diameters of the light spots after two parallel light beams symmetrically incident about the principal optical axis are emitted by the pupil separator; α - angle between the first pupil separation element and the second pupil separation element; θ - angle between two parallel light beams symmetrically incident about the principal optical axis. Specific embodiments

[0011] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. It should be noted that, without conflict, the various features in the embodiments of the present application can be combined with each other, and the combined embodiments are still within the protection scope of the present application.

[0012] In the description of the present application, it should be noted that the orientation or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and thus should not be construed as limiting the present application. In addition, the terms "first", "second", "third", etc. are only used for descriptive distinction and should not be construed as indicating or implying relative importance.

[0013] On the one hand, an embodiment of the present application provides a fundus imaging system, including a pupil separator. As Figure 1 shown, the pupil separator includes a first pupil separation element 10 and a second pupil separation element 20 arranged at an angle. A first pupil 11 is provided on the first pupil separation element 10, and a second pupil 21 is provided on the second pupil separation element 20. Parallel light beams in different directions scanned are emitted through the first pupil 11 of the first pupil separation element 10 and the second pupil 21 of the second pupil separation element 20. Among them, the diameters of the light spots after two parallel light beams symmetrically incident about the principal optical axis are emitted by the pupil separator are the same.

[0014] As Figure 1As shown, the pupil separator includes two optical parts, namely a first pupil separation element 10 and a second pupil separation element 20. Along the light propagation direction of the principal optical axis, the first pupil separation element 10 is in the front and the second pupil separation element 20 is in the rear. The first pupil separation element 10 and the second pupil separation element 20 are connected at a preset angle.

[0015] Parallel light beams in different directions emitted by scanning are incident on the pupil separator. The parallel light beams in different directions are sequentially emitted after passing through the first pupil 11 of the first pupil separation element 10 and the second pupil 21 of the second pupil separation element 20. Among them, the light beam incident on the surface of the first pupil separation element 10 is reflected, and the light beam incident on the surface of the second pupil separation element 20 after passing through the first pupil 11 of the first pupil separation element 10 is also absorbed. In this way, the parallel light beams in different directions still exit in the original parallel light direction after passing through the first pupil 11 and the second pupil 21. Due to the limitation of the outer contour of the transmitted light beam by the first pupil 11 and the second pupil 21, as Figure 1 shown, when two parallel light beams symmetrically incident with the principal optical axis as the center are compared, after passing through the first pupil 11 and the second pupil 21 and exiting, the diameters of the received light spots are d1 and d2 respectively, and d1 and d2 are the same. With such a structural design of the pupil separator, it can effectively ensure that within a certain incident light angle range, the numerical aperture consistency of the light spots of the parallel light beams in different directions after exiting the pupil separator is relatively good, providing stable beam modulation conditions for the pupil separator to be arranged in the fundus imaging system to obtain better imaging quality.

[0016] Among them, the setting position and shape of the first pupil 11 on the first pupil separation element 10, the setting position and shape of the second pupil 21 on the second pupil separation element 20, and the specific angle between the first pupil separation element 10 and the second pupil separation element 20 are not strictly limited in the embodiments of the present application. Those skilled in the art can make reasonable settings according to the parameter conditions of the incident light beam and the parameter requirements of the exiting light beam.

[0017] The pupil separator provided in the embodiment of the present application comprises a first pupil separation element 10 and a second pupil separation element 20 arranged at an angle, the first pupil separation element 10 is provided with a first pupil hole 11, and the second pupil separation element 20 is provided with a second pupil hole 21, and parallel light emitted in different directions by scanning is sequentially emitted through the first pupil hole 11 of the first pupil separation element 10 and the second pupil hole 21 of the second pupil separation element 20, wherein the diameters of the light spots of the two beams of parallel light symmetrically incident with the main optical axis as the center after being emitted by the pupil separator are the same. The pupil separator of the embodiment of the present application is applied to a fundus imaging system, the illumination light beam is reflected from the surface of the first pupil separation element 10 to the human eye and then reflected by the fundus, the light beam reflected from the fundus is scanned and emitted to form parallel light in different directions within the scanning range, and the multi-angle parallel light symmetrical with the main optical axis as the center is incident on the pupil separator, and sequentially emitted through the first pupil hole 11 of the first pupil separation element 10 and the second pupil hole 21 of the second pupil separation element 20, and is imaged by the incident camera. Among them, the diameters of the two beams of parallel light symmetrically incident with the main optical axis as the center are the same after being emitted through the pupil separator, so that the light intensity of the entire field of view is uniform, the numerical aperture in different fields of view is consistent, the uniformity of the light spot is improved, the clarity of the image is more consistent in various places, and the quality of the image is better.

[0018] In some feasible implementations of the present application, such as Figure 2 As shown, the angle α between the first pupil separation element 10 and the second pupil separation element 20 is 45°, the first pupil separation element 10 is 45° to the main optical axis, and the second pupil separation element 20 is perpendicular to the main optical axis.

[0019] like Figure 2As shown, the pupil separator of the embodiment of the present application is arranged in the optical path to modulate the light beam, and the angle α between the first pupil separation element 10 and the second pupil separation element 20 is 45°. The second pupil separation element 20 is arranged perpendicular to the main optical axis, and the angle between the first pupil separation element 10 and the main optical axis is also 45°. When the pupil separator of the embodiment of the present application is arranged in the fundus imaging system, the light beam reflected by the fundus is scanned and emitted to form parallel light in different directions within the scanning range, and the multi-angle parallel light symmetrical with the main optical axis as the center is incident on the pupil separator, wherein the two beams of parallel light symmetrically incident with the main optical axis as the center are emitted after passing through the first pupil hole 11 and the second pupil hole 21, and the diameters d1 and d2 of the two emitted light beams are equal. The two beams of parallel light that are symmetrically incident with the main optical axis as the center can achieve the same diameter of the symmetrically emitted light beams after passing through the pupil separator, which can make the light intensity of the entire field of view uniform and improve the uniformity of the light spot emitted through the pupil separator. Therefore, when the pupil separator of the embodiment of the present application is applied to the fundus imaging system and is set corresponding to the main optical axis in the above manner, the clarity of the image received in the camera of the fundus imaging system can be more consistent in various places, and the imaging quality is better.

[0020] In some feasible implementations of the present application, such as Figure 3 As shown, the second pupil separation element 20 is arranged on a plane where the intersection of two parallel light beams symmetrically incident with the main optical axis as the center and the main optical axis is located.

[0021] Reference Figure 3 As shown, Figure 3 In the figure, two beams of parallel light symmetrically incident with the main optical axis as the center and having the same angle with the main optical axis are shown. After the two beams of parallel light are incident, they cross and then emerge. The second pupil separation element 20 of the pupil separator is set at the plane where the intersection of the two beams of parallel light is located. In this way, it can be ensured that the diameters of the two paired beams of parallel light incident at the same angle on both sides of the main optical axis are the same after passing through the pupil separator. When the pupil separator of the embodiment of the present application is applied to the fundus imaging system, when the light beams emitted through the pupil separator reach the camera, the numerical apertures of the symmetrical fields of view are consistent, so that the quality of the acquired fundus image is better.

[0022] In some feasible implementations of the present application, such as Figure 4 As shown, the pupil separator also includes a receiving substrate 30, and the bottoms of the first pupil separation element 10 and the second pupil separation element 20 are respectively fixed on the two side edges of the receiving substrate 30, wherein the first pupil separation element 10 is 45° with the receiving substrate, and the second pupil separation element 20 is perpendicular to the receiving substrate 30; the center of the first pupil 11 of the first pupil separation element 10 and the center of the second pupil 21 of the second pupil separation element 20 are both located on the main optical axis.

[0023] likeFigure 4 As shown, the pupil separator further includes a receiving substrate 30 respectively connected to the first pupil separation element 10 and the second pupil separation element 20. The first pupil separation element 10 and the second pupil separation element 20 are accurately fixed in a specific angular relationship through the receiving substrate 30, so that the pupil separator of the embodiment of the present application is convenient to be arranged and finely adjusted in a working optical path such as a fundus imaging system.

[0024] Among them, the setting structures of the receiving substrate 30 with the first pupil separation element 10 and the second pupil separation element 20 include a variety of specific structural design schemes. For example, in some feasible embodiments of the present application, still referring to Figure 4 As shown, the top of the first pupil separation element 10 is connected to the top of the second pupil separation element 20. In this way, the first pupil separation element 10 having the first pupil 11 and the second pupil separation element 20 having the second pupil 21 can be designed and manufactured respectively first, and then the first pupil separation element 10 and the second pupil separation element 20 are respectively arranged on the receiving substrate 30 and the top of the second pupil separation element 20 is connected. The process of installation, debugging and calibration is smooth, convenient and easy to operate.

[0025] In addition, in some other feasible embodiments of the present application, as Figure 5 shown, there is a preset interval between the top of the second pupil separation element 20 and the upper edge of the first pupil 11 of the first pupil separation element 10. The space between the top of the second pupil separation element 20 and the upper edge of the first pupil 11 of the first pupil separation element 10 serves as the second pupil 21 of the second pupil separation element 20, and the preset interval is the diameter of the second pupil 21.

[0026] As Figure 5As shown, for the pupil separator designed in this way, the part of the first pupil separation element 10 above the first pupil 11 is shared with the second pupil separation element 20, making the structural size of the entire pupil separator further compact and effectively reducing the size in the optical axis direction. When the pupil separator of the embodiment of the present application is applied to an optical path system, it is more conducive to being flexibly arranged in a miniaturized optical device. The second pupil separation element 20 can be understood as an integral plate surface structure in this solution. The light-receiving surface of this plate surface structure can absorb light. For example, the light-receiving surface of this plate surface structure is coated with a black or dark color, and the light irradiated on the light-receiving surface of this plate surface structure is absorbed. The space in the vertical direction between the top of the second pupil separation element 20 and the upper edge of the first pupil 11 serves as the second pupil 21. In this way, taking the main optical axis as the center of symmetry, the upper ends of two parallel light beams incident at the same angle with the main optical axis are bounded by the occlusion of the upper edge of the first pupil 11, and the lower ends of the two parallel light beams are bounded by the lower edge of the second pupil 21, that is, the end of the second pupil separation element 20. The diameters of the two parallel light beams emitted in this way are the same.

[0027] As Figure 6 As shown, in the pupil separator of the embodiment of the present application, the second pupil separation element 20 is hinged to the first pupil separation element 10. At one end of the first pupil separation element 10, a support structure is extended for connecting and fixing with the frame structure of the fundus imaging system. The pupil separator is fixedly arranged in the fundus imaging system through the support structure. Among them, the first pupil separation element 10 includes a reflective sheet with a hollow part. The hollow part of the reflective sheet forms a first pupil 11 of the first pupil separation element 10. Hinge shafts located in the plane of the reflective sheet are arranged on opposite sides of the hollow part on the reflective sheet. The second pupil separation element 20 is hingedly arranged in the hollow part through the hinge shafts. A second pupil 21 with a preset diameter is formed at the center of the second pupil separation element 20. Since the second pupil separation element 20 is hinged to the first pupil separation element 10, the second pupil separation element 20 can rotate relative to the hinge shafts, and the included angle between the second pupil separation element 20 and the first pupil separation element 10 can be adjusted.

[0028] Please refer to Figure 7 As shown, the included angle between the first pupil separation element 10 and the second pupil separation element 20 is adjusted to a preset included angle. Two parallel light beams incident symmetrically with the main optical axis at the same angle with the main optical axis cross and then exit after incidence. The first pupil 11 and the second pupil 21 cross and partially overlap. The two parallel light beams are respectively restricted by the first pupil separation element 10 and the second pupil separation element 20. Among them, part of the light beam that can pass through the first pupil 11 and the second pupil 21 exits. In this way, on both sides symmetric about the main optical axis, for a pair of two parallel light beams incident at the same angle, after passing through Figure 7The diameters of the light beams emitted after the pupil separator are the same. When the pupil separator of the embodiment of the present application is applied to a fundus imaging system, when the light beams emitted through the pupil separator reach the camera, the numerical apertures of the symmetrical fields of view are consistent, so that the quality of the acquired fundus images is better.

[0029] And refer to Figure 6 It can be seen that in the solution of the pupil separator of the present embodiment, the angle between the first pupil separation element 10 and the second pupil separation element 20 can be conveniently adjusted and fixed by a hinge axis. By adjusting the different angles between the first pupil separation element 10 and the second pupil separation element 20, the fundus imaging system to which the pupil separator of the embodiment of the present application is applied can more flexibly match the requirements of two pairs of parallel light beams incident at the same specific angle in different scenes, and both can be emitted as light beams with the same diameter, so that the pupil separator of the embodiment of the present application can be applied to fundus imaging systems with various different parameter conditions through simple adjustment and fixation, and the operation is convenient and the precision is high.

[0030] On the other hand, an embodiment of the present application provides a fundus imaging system, including any of the pupil separators described above. The illumination light beam is reflected from the surface of the first pupil separation element 10 to the human eye, and then reflected from the fundus. The light beam reflected from the fundus is scanned and emitted to form parallel light in different directions within the scanning range. The multi-angle parallel light symmetrically centered on the main optical axis enters the pupil separator, and sequentially passes through the first pupil hole 11 of the first pupil separation element 10 and the second pupil hole 21 of the second pupil separation element 20, and then converges to the camera for imaging. Among them, the diameters of the light spots of the two beams of parallel light symmetrically incident with the main optical axis as the center after being emitted from the pupil separator are the same, so that the light intensity of the entire field of view is uniform, the numerical aperture is consistent in different fields of view, the uniformity of the light spot is improved, the clarity of the image is relatively consistent, and the quality of the image is better. It provides a clearer and more accurate image basis for the diagnosis and treatment of ophthalmic diseases. It can thus provide a clearer and more accurate image basis for the diagnosis and treatment of ophthalmic diseases.

[0031] In some feasible implementations of the present application, such as Figure 8 As shown, the fundus imaging system includes a pupil separator 01, a scanning galvanometer 02 and a camera 03. The light beam reflected by the fundus is scanned and emitted by the scanning galvanometer 02, and multi-angle parallel light symmetrical with the main optical axis as the center enters the pupil separator 01 and enters the camera 03 to form an image.

[0032] like Figure 8As shown in the figure, the fundus imaging system according to the embodiment of the present application includes a scanning galvanometer 02, a pupil separator 01, and a camera 03. Before the scanning galvanometer 02 and the camera 03, there are also a scanning mirror group and an imaging mirror group for modulating the incident light path. In some feasible embodiments of the present application, the fundus imaging system further includes an illumination module ( Figure 8 not shown in the figure). The illumination module includes a light source, an optical unit for collimating, focusing, and homogenizing the modulated light beam emitted by the light source, and a diaphragm for constraining the contour of the emitted light beam. For example, the wavelength range of the light beam emitted by the light source is between 400 nm and 900 nm, the focal length range of the collimating lens is set between 6 mm and 30 mm, and the focal length range of the focusing unit is set between 20 mm and 100 mm. Among them, the optical unit for homogenizing modulation can adopt optical elements such as an optical fiber bundle, a rectangular quartz rod, and a diffusing sheet. The light beam emitted by the light source is emitted through the diaphragm after being homogenized. The setting position of the diaphragm is conjugate to the measured fundus. The diaphragm described here is an illumination diaphragm, usually rectangular. In the present application, a waist-shaped diaphragm and a stepped diaphragm will be provided. The light beam emitted through the diaphragm is collimated and then reflected by the surface of the pupil separator to the scanning galvanometer 02. After passing through the scanning mirror group, it is converged by the eyepiece group to the pupil position of the human eye and irradiated to the fundus, forming a rectangular illumination spot on the fundus for wide-line illumination scanning of the measured fundus. The return light signal scattered from the fundus reaches the eyepiece group through the pupil, is reflected by the dichroic mirror to the scanning mirror group after passing through the eyepiece group, and the light beam scanned out from the scanning mirror group is scanned out by the scanning galvanometer 02 to the pupil separator 01. The light beam emitted from the light-transmitting part at the center of the pupil separator 01 is converged by the imaging mirror group to the camera 03. The fundus and the camera 03 are in a conjugate relationship. In this way, it can be ensured that the light signal returned from the fundus, after passing through the light-transmitting part at the center of the pupil separator 01, that is, the first pupil 11 of the first pupil separation element 10 and the second pupil 21 of the second pupil separation element 20, the structure for constraining the contour of the emitted light beam as a diaphragm is located at the intersection of the light beams at the same symmetric angle, and it can be ensured that on both symmetric sides centered on the principal optical axis, the diameters of the light beam spots emitted at the symmetric angles are the same, and the numerical apertures of the light beams emitted at the symmetric angles are the same in the symmetric field of view after reaching the camera 03, so that the image quality of the camera 03 is more uniform and clear, and the imaging quality is better.

[0033] In some feasible embodiments of the present application, please refer to Figure 5 as shown in the figure, the light beam imaged in the camera 03 satisfies the following relationship: d2 = d1 = d0 * cos(θ / 2) (1); wherein, d1 and d2 are respectively the diameters of the light beam spots emitted by the pupil separator 01 for two parallel light beams symmetrically incident centered on the principal optical axis, d0 is the diameter of the second pupil 21, and θ is the included angle between two parallel light beams symmetrically incident centered on the principal optical axis.

[0034] As Figure 5 shown, the pupil separator 01 of the embodiment of the present application is disposed in the fundus imaging system. The centers of the first pupil 11 and the second pupil 21 of the pupil separator 01 are both located on the principal optical axis. Moreover, the second pupil separation element 20 is disposed at the plane where the foci of two parallel light beams symmetrically incident about the principal optical axis and having the same angle with the principal optical axis are located. The diameter d0 of the second pupil 21 is located at the intersection of the two parallel light beams. If the angle between the two parallel light beams symmetrically incident about the principal optical axis is θ, the imaging light beam emitted from the pupil separator 01 to the camera 03 satisfies the relation (1). That is, on the premise that the numerical apertures of the light beams are consistent in the symmetric field of view when reaching the camera 03, it is also possible to maximize the light flux in the optical path system.

[0035] The foregoing are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. An fundus imaging system, comprising a pupil separator, characterized in that, The pupil separator includes a first pupil separation element and a second pupil separation element arranged at an included angle. A first pupil is provided on the first pupil separation element, and a second pupil is provided on the second pupil separation element. Parallel light beams in different directions emitted by scanning exit through the first pupil of the first pupil separation element and the second pupil of the second pupil separation element. Among them, the diameters of the light spots of two parallel light beams symmetrically incident centered on the principal optical axis are the same after exiting through the pupil separator.

2. The fundus imaging system according to claim 1, characterized in that, The included angle between the first pupil separation element and the second pupil separation element is 45°, the first pupil separation element is at 45° with the principal optical axis, and the second pupil separation element is perpendicular to the principal optical axis.

3. The fundus imaging system according to claim 2, wherein The second pupil separation element is arranged in the plane where the intersection of two parallel light beams symmetrically incident centered on the principal optical axis and the principal optical axis is located.

4. The fundus imaging system according to claim 2, characterized in that, The pupil separator further includes a receiving substrate. The bottoms of the first pupil separation element and the second pupil separation element are respectively fixed on two side edges of the receiving substrate. Among them, the first pupil separation element is at 45° with the receiving substrate, and the second pupil separation element is perpendicular to the receiving substrate; the centers of the first pupil of the first pupil separation element and the second pupil of the second pupil separation element are both located on the principal optical axis.

5. The fundus imaging system according to claim 4, characterized in that, The top of the first pupil separation element is connected to the top of the second pupil separation element.

6. The fundus imaging system according to claim 4, characterized in that, There is a preset interval between the top of the second pupil separation element and the upper edge of the first pupil of the first pupil separation element. The space between the top of the second pupil separation element and the upper edge of the first pupil of the first pupil separation element serves as the second pupil of the second pupil separation element, and the preset interval is the diameter of the second pupil.

7. The fundus imaging system according to claim 1, wherein The pupil separator further includes a support structure for fixedly connecting with the frame structure of the fundus imaging system. The first pupil separation element is fixedly connected to the support structure. The first pupil separation element includes a reflective sheet with a hollow part. The hollow part of the reflective sheet serves as the first pupil of the first pupil separation element. Hinge shafts located in the plane of the reflective sheet are provided on opposite sides of the hollow part on the reflective sheet. A second pupil separation element is hingedly arranged in the hollow part through the hinge shafts, and a second pupil with a preset diameter is formed at the center of the second pupil separation element.

8. The fundus imaging system according to any one of claims 1-7, characterized in that, The fundus imaging system further includes a scanning galvanometer and a camera. The light beam reflected by the fundus exits after being scanned by the scanning galvanometer, and parallel light beams at multiple angles symmetrically centered on the principal optical axis are incident on the pupil separator and then incident on the camera for imaging.

9. The fundus imaging system according to claim 8, wherein, The light beam imaged in the camera satisfies the following relational expression: d2 = d1 = d0 * cos(θ / 2); Among them, d1 and d2 are respectively the diameters of the light spots of two parallel light beams symmetrically incident centered on the principal optical axis after exiting through the pupil separator, d0 is the diameter of the second pupil, and θ is the included angle between two parallel light beams symmetrically incident centered on the principal optical axis.

10. The fundus imaging system according to claim 8, wherein It further includes an illumination module. The illumination module emits an illumination light beam towards the pupil separator. The illumination light beam is reflected by the surface of the first pupil separation element to the human eye and then reflected by the fundus.

Images